In image diagnosis, it has been known that the accumulation of asbestos inhaled by an object in lungs can be found as thickness abnormality of a lung wall or chest wall. For example, Patent Document 1 discloses the technique for implementing image processing in a chest X-ray image to appropriately detect asbestos.
Patent Document 1: JP-A-2007-244738
Further, the illness attributed to asbestos can be diagnosed by a tomographic image obtained by an X-ray CT apparatus when the condition of illness becomes serious such as mesothelioma. Doctors have been diagnosing accumulation or illness of asbestos in patients' lungs by visual evaluation, by measuring the abnormality of thickness of lung wall or chest walls on images.